A Second Skin
Fire-resistant apparel acts as a layer of clothing that can literally save your skin — and is a must for many workers.
It is a layer of clothing that can literally save your skin. Fire-resistant (FR) apparel is a must not only for electrical and utility workers, but also those who work with chemicals, oil and gas and pulp and paper.
As with any PPE, one should not assume that a single-layer of FR garment will provide adequate protection against all thermal hazards or is appropriate for all tasks. “It is important to conduct a thorough workplace risk assessment to determine the level of protection necessary for your garments,” says Greg Kelly, Western Canada Market Manager at Westex Inc. in Edmonton.
The selection of materials and fabrics for FR clothing is diverse. Fire-resistant fabrics can be broadly grouped into two types: inherent and treated. Inherent fabrics get its flame-resistant properties when the fibres are created without any chemical coating or treatment. Aramid fibres, which include Nomex and Kermel, are the most common type.
“Materials do not have to be a 100 per cent blend of inherent fabrics in order to be considered flame resistant, as they can be mixed with a low amount of cotton, nylon or spandex,” says Leslie Molin, market-segment manager for personal safety with Levitt Safety in Oakville. “By adding secondary fabrics, the comfort, durability, moisture management, breathability and stretch can be greatly improved.”
Treated fabrics, on the other hand, are typically made of 88 per cent cotton and 12 per cent nylon or polyester, which gives them the commonly used name of 88/12. “Cotton itself is flammable, so the fabric needs to go through a process where the fabric is treated or dipped with a flame-resistant chemical. This efficient, flame-resistant treatment produces the same flame-resistance protection as inherent fabrics.”
While FR clothing will self-extinguish or burn very slowly if it catches fire, that does not mean it is arc-rated to protect against an electrical arc, which is an explosive burst of heat and light caused by a sudden, uncontrolled current passing through the air.
An integral part of an electrical-safety program is performing a study to identify what the electrical hazards are. If there is a potential for an arc flash, it is important to determine how much incident energy, measured in calories, will be released if an arc flash occurs.
Arc-flash PPE is determined by a category rating or calculating the amount of energy that will be released in the arc flash, in calories per centimeter squared. A calorie is the amount of energy required to raise the temperature of one gram of water by one degree Celsius at standard pressure.
“This information also allows you to set your arc-flash protection boundaries, which will tell you how far you need to be away from the source of an arc flash to avoid injuries if one should occur,” Molin says.
This analysis can be performed in-house by a company’s electrical safety committee or software programs that can calculate the values, or outsourced to an electrical specialist that can provide a complete hazard analysis.
“Most people think of an arc-flash suit or ‘bomb suit’ when they hear the term ‘arc flash PPE’,” Molin says. “But basic FR coveralls tend to have around six to eight calories of protection and are suitable for protecting against lower energy arc-flash risks. There are also arc-flash suits that offer up to 140 calories of protection, which is well beyond the often used category four level of protection at 40 calories.”
“Specifying the right arc-rated or FR fabric and garment design, in addition to conducting thorough workplace-risk assessments, can help to minimize injuries in the event of an arc flash or flash fire,” Kelly says.
Evaluating the manufacturer’s fabrics, performance in industry standards and quality support programs are also key to a successful FR program, he adds.
Apart from protecting against fire and arc flash, the need to be visible is also important for workers who operate in low light conditions or areas with vehicular and pedestrian traffic. For these workers, they will need reflective strips that can be attached onto their FR apparel.
For this purpose, 3M™ Scotchlite™ Reflective Material is designed to enhance the visibility of the person wearing FR clothing in occupational settings like oil and gas, utilities and mines where moving equipment and weather conditions can hamper visibility. “3M Scotchlite Reflective material help keep that person in the driver’s eye,” says Ruth Cockwill, high visibility apparel specialist with 3M Scotchlite Reflective Materials in 3M Canada in Edmonton.
The reflective strips can be sewn onto a garment or attached to it by applying heat. “Typically, it will go on something that is worn every day like a safety vest, a parka jacket, coverall and overalls,” she adds.
Like any PPE, a risk assessment needs to be done to identify which type of workers need reflective strips on their FR apparel. “Second, determine what regulations and standards apply,” Cockwill says. For instance, some workers might need arc-flash protection, while others benefit from protection against steam, hot liquids and flash fire, which is a sudden, intense fire caused by the ignition of a mixture of air and a dispersed flammable substance such as dust or combustible liquid or flammable gas.
Another selection criterion is how the garment is to be laundered. Arc-rated or FR garments can be professionally laundered through rental or leasing programs or washed at home. “The proper care for a garment depends on the laundering requirements of the fabric, so it is important to know the fabric in your garment and launder it according to the care instructions,” Kelly says. Many industrial laundries have services to monitor and maintain PPE, he adds.
Kelly advises against removing laundry or garment labels, as these tags provide important laundry, standards and specifications that the wearer needs for future reference. “Don’t wear FR garments that are heavily soiled or contaminated. This may negatively impact the fabric’s flame-resistance properties,” he cautions.
UP TO STANDARD
One new development in the FR-apparel market is the inclusion of Conformity Assessment Standards as new requirements for FR arc-rated garments. In 2018, updated revisions of the NFPA 70E and CSA Z462 Workplace Electrical Safety Standards were published. These new standards include requirements for all suppliers and manufacturers to demonstrate their level of conformity to all applicable standards.
“The greatest unknown about FR arc-rated apparel is whether… the garment will perform as expected when exposed to a thermal hazard,” Molin says. “The only way anyone can validate a supplier or a manufacturer’s claim is to destroy their FR arc-rated garment in a testing laboratory.”
With the introduction of Conformity Assessment Standards, end users can adopt these new requirements as part of product specifications. “This change will require the supplier or manufacturer to provide a declaration of conformity, meaning they are now more accountable for the performance of their products,” Molin says. “The result should be an increased level of confidence in the FR arc-rated protection that employers procure and provide to their workers.”
Having the right protection product is important, but so is knowing how to use them properly. One of the common misconceptions surrounding FR apparel is that the FR qualities of a treated garment can be washed out. “This was the case in the past,” Molin says. “However with most treated garments on the market now, you have lifetime FR that is locked into the fabric.”
There is also the perception that FR garments are hot and heavy. Molin points to great strides in fabric technology, which can engineer fabrics that are of lighter weight and more comfortable.
“The goal in designing FR garments is to develop the lightest-weight fabric without compromising its protection or durability,” Molin says, citing Oberon’s ultra-lightweight arc-rated fabric systems that use a black outer-shell material, resulting in a higher arc rating without compromising the strength of the materials.
Another breakthrough product is the two-piece “Suit-All” Coverall from IFR Workwear. This product provides a custom fit, especially for women, through sizing pairing options. “These coveralls are not only more comfortable to wear in the field, but also safer,” Molin says.
One company that recently showcased its expanded line of performance FR fabrics at a safety conference and expo in New Orleans is Westex by Milliken. Westex® DH keeps workers cooler, drier and more comfortable by utilizing a unique woven blend structure to provide optimal moisture management and nearly four times more breathability than other FR fabric when tested against ASTM D737 protocol. The fabric is NFPA 2112 certified and provides NFPA 70E Category 2 protection.
“Engineered for the oil and gas and electrical industries, Westex® branded fabrics cover a multitude of jobsite hazards, including offering proven protection to help mitigate impacts of short-term thermal exposures like flash fire and arc flash,” says Tom Moore, national sales director for the Westex by Milliken. “The breadth of Westex fabric portfolio allows companies to customize their FR garment needs with key characteristics that are important to the wearer or the environment without compromising on safety.”
Common mistakes associated with the use of FR apparel include wearing the wrong fabric for the wrong task, not developing a management system for maintenance and the lack of education on how to wash FR apparel.
“If a worker needs to add a jacket or rainwear over an FR apparel, these garments need to be made from FR materials,” Molin advises. They also need to ensure that sleeves are not rolled up. Shirts, jackets and coveralls should also be closed fully at the neck, she adds.
Wearers should also inspect FR garments regularly for holes, rips, tears, thinning or permanent stains.
Jean Lian is the former editor of OHS Canada.
Follow us on Twitter @OHSCanada